Journal ArticleDOI
MAMMALS THAT BREAK THE RULES: Genetics of Marsupials and Monotremes
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TLDR
In many features, it appears that humans and, particularly, mice are the weird mammals that break more general mammalian, or even vertebrate rules.Abstract:
▪ Abstract Marsupials and monotremes, the mammals most distantly related to placental mammals, share essentially the same genome but show major variations in chromosome organization and function. Rules established for the mammalian genome by studies of human and mouse do not always apply to these distantly related mammals, and we must make new and more general laws. Some examples are contradictions to our assumption of frequent genome reshuffling in vertebrate evolution, Ohno's Law of X chromosome conservation, the Lyon Hypothesis of X chromosome inactivation, sex chromosome pairing, several explanations of Haldane's Rule, and the theory that the mammalian Y chromosome contains a male-specific gene with a direct dominant action on sex determination. Significantly, it is not always the marsupials and monotremes (usually considered the weird mammals) that are exceptional. In many features, it appears that humans and, particularly, mice are the weird mammals that break more general mammalian, or even vertebr...read more
Citations
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X-inactivation profile reveals extensive variability in X-linked gene expression in females
TL;DR: A comprehensive X-inactivation profile of the human X chromosome is presented, representing an estimated 95% of assayable genes in fibroblast-based test systems, and suggests a remarkable and previously unsuspected degree of expression heterogeneity among females.
Journal ArticleDOI
The non-coding Air RNA is required for silencing autosomal imprinted genes
TL;DR: The results indicate that non-coding RNAs have an active role in genomic imprinting, by inserting a polyadenylation signal that truncates 96% of the RNA transcript, that Air RNA is required for silencing.
Journal ArticleDOI
Four Evolutionary Strata on the Human X Chromosome
Bruce T. Lahn,David C. Page +1 more
TL;DR: The ages of individual X-Y gene pairs and the locations of their X members on the X chromosome were found to be highly correlated and age decreased in stepwise fashion from thedistal long arm to the distal short arm in at least four "evolutionary strata".
Journal ArticleDOI
Functional coherence of the human Y chromosome.
Bruce T. Lahn,David C. Page +1 more
TL;DR: A systematic search of the nonrecombining region of the human Y chromosome (NRY) identified 12 novel genes or families, 10 with full-length complementary DNA sequences, which may account for infertility among men with Y deletions.
Journal ArticleDOI
X-chromosome inactivation: counting, choice and initiation
Philip Avner,Edith Heard +1 more
TL;DR: In many sexually dimorphic species, a mechanism is required to ensure equivalent levels of gene expression from the sex chromosomes, and in mammals, such dosage compensation is achieved by X-chromosome inactivation, a process that presents a unique medley of biological puzzles.
References
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Journal ArticleDOI
Gene Action in the X -chromosome of the Mouse ( Mus musculus L.)
TL;DR: Ohno and Hauschka1 showed that in female mice one chromosome of mammary carcinoma cells and of normal diploid cells of the ovary, mammary gland and liver was heteropyKnotic and suggested that the so-called sex chromatin was composed of one heteropyknotic X-chromosome.
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A gene from the human sex-determining region encodes a protein with homology to a conserved DNA-binding motif
Andrew H. Sinclair,Berta P,Berta P,M. S. Palmer,Hawkins,B. Griffiths,Smith Mj,Foster Jw,Foster Jw,A.-M. Frischauf,Robin Lovell-Badge,Peter N. Goodfellow +11 more
TL;DR: A search of a 35-kilobase region of the human Y chromosome necessary for male sex determination has resulted in the identification of a new gene, termed SRY (for sex-determining region Y) and proposed to be a candidate for the elusive testis-d determining gene, TDF.
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Male development of chromosomally female mice transgenic for Sry
TL;DR: It is shown that Sry on a 14-kilobase genomic DNA fragment is sufficient to induce testis differentiation and subsequent male development when introduced into chromosomally female mouse embryos.
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Sex ratio and unisexual sterility in hybrid animals
TL;DR: When in theF1 offspring of a cross between two animal species or races one sex is absent, rare, or sterile, that sex is always the heterozygous sex.
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A gene mapping to the sex-determining region of the mouse Y chromosome is a member of a novel family of embryonically expressed genes
John Gubbay,Jérôme Collignon,Peter Koopman,Blanche Capel,Androulla Economou,Andrea Münsterberg,Nigel Vivian,Peter N. Goodfellow,Robin Lovell-Badge +8 more
TL;DR: A gene mapping to the sex-determining region of the mouse Y chromosome is deleted in a line of XY female mice mutant for Tdy, and is expressed at a stage during male gonadal development consistent with its having a role in testis determination.